舵型变化对船舶操纵性能的影响

介绍采用常规舵及整流尾组合舵两种方案的操纵性试验结果 ,探讨不同舵型对操纵性能带来的影响 ,最后归纳舵型变化对改善操纵性能的作用。     

川江及三峡库区变吃水干散货船的优化论证

川江及三峡库区航道水深季节性变化大,为了充分利用水深条件,船舶多采用变吃水设计,船舶航行时载况的变化会引起主机、螺旋桨的工况发生变化,因而船舶营运经济性的计算有别于常规船舶,对船舶营运经济计算中载货量、航速及经济参数进行分析,实例计算结果令人满意。     

城市轨道交通预制箱梁设计概算编制

以北京市和广州市轨道交通工程为例，详细介绍了大吨位整孔预制箱梁预制和架设的概算编制方法，指出机械地套用地方市政定额是不科学和不切实际的，应根据工程的具体工艺工法借用铁路工程定额，达到合理确定工程造价的目的。     

2万吨级多用途船船型试验研究

对2万吨级多用途船船型进行了试验研究，该船与相近吨位船舶相比，傅氏数高，方型系数大，船型优化设计有一定的难度，在吸收国内外先进经验，分析上海船研所同类型多用途船船型研究资料的基础上，先后设计了2个方案的球艏线型，通过试验分析比较，优选出推荐船型。优选船型有效地解决了该船的快速性问题，性能优良，可供船舶设计及建造部门使用。     

MZ32型移动模架造桥机在秦沈客运专线的应用

秦沈客运专线小凌河特大桥主河槽 3 2m双线预应力混凝土箱梁施工采用中铁大桥局自行研制的MZ3 2型移动模架造桥机原位整孔现浇的方案 ,在铁路桥梁施工中尚属首次。简要介绍该造桥机的构造、原理、施工工艺     

轻轨车辆系列型谱研究

在详细调查我国各大城市公交客流的基础上,对客流进行了科学规划,并以此为基础,对轻轨车辆的几何、动力、舒适性参数进行了详细的计算分析,制定了适合我国国情的轻轨车辆系列型谱。综合以上分析结果,结合我国目前经济技术条件,并参考国外车辆发展状态,制定了包括2.6m宽和2.8m宽的二大系列的轻轨车辆系列型谱标准。     

Relationships between Microbial Growth Parameters and Shelf Life of MAP Sliced Onions

Onion (Allium Cepa L.), abundant in essen-tial minerals and trace elements, is favorable in theworld. Fresh sliced onions could be eaten either di-rectly or after processed. These fresh cut onionsare very acceptable by consumers who look forhealthy food and have little preparation time[1]. Storage of intact onions has been widely stud-ied. Croci et al.[2]studied the effects of irradiationand long-term storage on the quality of Valencianasintética 14 onion variety during two consecutiveyears…     

城市轨道车辆空调问题的探讨

本文通过分析城市轨道车辆的特点,对其空调热负荷的计算和室内舒适性条件进行了研究,并对如何确定外气温湿度、载客量、室内温湿度、新风量、粉尘含量、微风速等计算参数提出了建议.     

Development of a hull form definition tool with a related knowledge-based advisory system

The development of a parametric hull form design system utilizing combined knowledge-based and objectoriented methodologies, approaches, and techniques is the major purpose of this research. One objective was the development of a powerful, intuitive, and parameter-based hull definition system with a related hull definition advisory system that would provide useful and necessary advice to the user. Object and knowledge modeling activities were conducted during the analysis and design stage to facilitate the implementation of a hull design program and advisory system. The hull design system includes the generation of a geometric model from a process of aggregating simple user-selected shapes representing different boundaries. Design involves the capability to vary simple parameters such as entrance angles, length-breadth ratios, and radii to define local and general surface geometries. Hydrostatic calculations are included for analysis; results are referred to an advisory system for evaluation and the determination of the acceptability of parameters and analysis results. The advisory system includes a knowledge bases consisting of hull form databases, results of the statistical analysis of data, design parameter constraints, and expert knowledge acquired from designers, reference materials, and technical reports. Use of the design tool with the advisory system results in the rapid generation of hull forms and associated design evaluations. Flexibility in decision making results from the separation of the design system from the advisory system. The independence of the two systems allows for a wide range of user experience with experts using the design tool with minimal reference to the advisory system. On the other hand, the expertise and knowledge stored in the advisory system is fully available to inexperienced designers and users.